14. Code that prevents an InputMismatchException

• 
  double subtotal = 0.0;
  System.out.print("Enter subtotal:   ");
  if (sc.hasNextDouble())
  {
      subtotal = sc.nextDouble();
  }
  else
  {
      sc.nextLine();    // discard the entire line
      System.out.println(
          "Error! Invalid number. Try again.\n");
      continue;         // jump to the top of the loop
  }
  
  

  Console output:

  Enter subtotal:   $100
  Error! Invalid number. Try again.
  
  Enter subtotal: